Journal articles: 'Phage T3'

1

Serwer, Philip, Elena T. Wright, Jorge De La Chapa, and Cara B. Gonzales. "Basics for Improved Use of Phages for Therapy." Antibiotics 10, no. 6 (June 16, 2021): 723. http://dx.doi.org/10.3390/antibiotics10060723.

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Blood-borne therapeutic phages and phage capsids increasingly reach therapeutic targets as they acquire more persistence, i.e., become more resistant to non-targeted removal from blood. Pathogenic bacteria are targets during classical phage therapy. Metastatic tumors are potential future targets, during use of drug delivery vehicles (DDVs) that are phage derived. Phage therapy has, to date, only sometimes been successful. One cause of failure is low phage persistence. A three-step strategy for increasing persistence is to increase (1) the speed of lytic phage isolation, (2) the diversity of phages isolated, and (3) the effectiveness and speed of screening phages for high persistence. The importance of high persistence-screening is illustrated by our finding here of persistence dramatically higher for coliphage T3 than for its relative, coliphage T7, in murine blood. Coliphage T4 is more persistent, long-term than T3. Pseudomonas chlororaphis phage 201phi2-1 has relatively low persistence. These data are obtained with phages co-inoculated and separately assayed. In addition, highly persistent phage T3 undergoes dispersal to several murine organs and displays tumor tropism in epithelial tissue (xenografted human oral squamous cell carcinoma). Dispersal is an asset for phage therapy, but a liability for phage-based DDVs. We propose increased focus on phage persistence—and dispersal—screening.

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Sarkar, Probir, Dola Sengupta, Shantanu Basu, and Umadas Maitra. "Nucleotide sequence of a major class-III phage-T3 RNA-polymerase promoter located at 98.0% of phage-T3 genetic map." Gene 33, no. 3 (January 1985): 351–55. http://dx.doi.org/10.1016/0378-1119(85)90243-4.

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Pajunen, Maria, Saija Kiljunen, and Mikael Skurnik. "Bacteriophage φYeO3-12, Specific forYersinia enterocolitica Serotype O:3, Is Related to Coliphages T3 and T7." Journal of Bacteriology 182, no. 18 (2000): 5114–20. http://dx.doi.org/10.1128/jb.182.18.5114-5120.2000.

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Bacteriophage φYeO3-12 is a lytic phage of Yersinia enterocolitica serotype O:3. The phage receptor is the lipopolysaccharide O chain of this serotype that consists of the rare sugar 6-deoxy-l-altropyranose. A one-step growth curve of φYeO3-12 revealed eclipse and latent periods of 15 and 25 min, respectively, with a burst size of about 120 PFU per infected cell. In electron microscopy φYeO3-12 virions showed pentagonal outlines, indicating their icosahedral nature. The phage capsid was shown to be composed of at least 10 structural proteins, of which a protein of 43 kDa was predominant. N-terminal sequences of three structural proteins were determined, two of them showing strong homology to structural proteins of coliphages T3 and T7. The phage genome was found to consist of a double-stranded DNA molecule of 40 kb without cohesive ends. A physical map of the phage DNA was constructed using five restriction enzymes. The phage infection could be effectively neutralized using serum from a rabbit immunized with whole φYeO3-12 particles. The antiserum also neutralized T3 infection, although not as efficiently as that of φYeO3-12. φYeO3-12 was found to share, in addition to the N-terminal sequence homology, several common features with T3, including morphology and nonsubjectibility to F exclusion. The evidence conclusively indicated that φYeO3-12 is the first close relative of phage T3 to be described.

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Ikebe, Tadayoshi, Akihito Wada, Yoshishige Inagaki, Kumiko Sugama, Rieko Suzuki, Daisuke Tanaka, Aki Tamaru, et al. "Dissemination of the Phage-Associated Novel Superantigen Gene speL in Recent Invasive and Noninvasive Streptococcus pyogenes M3/T3 Isolates in Japan." Infection and Immunity 70, no. 6 (June 2002): 3227–33. http://dx.doi.org/10.1128/iai.70.6.3227-3233.2002.

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ABSTRACT In Japan, more than 10% of streptococcal toxic shock-like syndrome (TSLS) cases have been caused by Streptococcus pyogenes M3/T3 isolates since the first reported TSLS case in 1992. Most M3/T3 isolates from TSLS or severe invasive infection cases during 1992 to 2001 and those from noninvasive cases during this period are indistinguishable in pulsed-field gel electropherograms. The longest fragments of these recent isolates were 300 kb in size, whereas those of isolates recovered during or before 1973 were 260 kb in size. These 260- and 300-kb fragments hybridized to each other, suggesting the acquisition of an about 40-kb fragment by the recent isolates. The whole part of the acquired fragment was cloned from the first Japanese TSLS isolate, NIH1, and its nucleotide sequence was determined. The 41,796-bp fragment is temperate phage φNIH1.1, containing a new superantigen gene speL near its right attachment site. The C-terminal part of the deduced amino acid sequence of speL has 48 and 46% similarity with well-characterized erythrogenic toxin SpeC and the most potent superantigen, SmeZ-2, respectively. None of 10 T3 isolates recovered during or before 1973 has speL, whereas all of 18 M3/T3 isolates recovered during or after 1992 and, surprisingly, Streptococcus equi subsp. equi ATCC 9527 do have this gene. Though plaques could not be obtained from φNIH1.1, its DNA became detectable from the phage particle fraction upon mitomycin C induction, showing that this phage is not defective. A horizontal transfer of the phage carrying speL may explain the observed change in M3/T3 S. pyogenes isolates in Japan.

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Buchholtz, F., and F. W. Schneider. "Computer simulation of T3 / T7 phage infection using lag times." Biophysical Chemistry 26, no. 2-3 (May 1987): 171–79. http://dx.doi.org/10.1016/0301-4622(87)80020-0.

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6

Pajunen, Maria I., Saija J. Kiljunen, M. E. Lotta Söderholm, and Mikael Skurnik. "Complete Genomic Sequence of the Lytic Bacteriophage φYeO3-12 of Yersinia enterocolitica Serotype O:3." Journal of Bacteriology 183, no. 6 (March 15, 2001): 1928–37. http://dx.doi.org/10.1128/jb.183.6.1928-1937.2001.

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ABSTRACT φYeO3-12 is a T3-related lytic bacteriophage of Yersinia enterocolitica serotype O:3. The nucleotide sequence of the 39,600-bp linear double-stranded DNA (dsDNA) genome was determined. The phage genome has direct terminal repeats of 232 bp, a GC content of 50.6%, and 54 putative genes, which are all transcribed from the same DNA strand. Functions were assigned to 30 genes based on the similarity of the predicted products to known proteins. A striking feature of the φYeO3-12 genome is its extensive similarity to the coliphage T3 and T7 genomes; most of the predicted φYeO3-12 gene products were >70% identical to those of T3, and the overall organizations of the genomes were similar. In addition to an identical promoter specificity, φYeO3-12 shares several common features with T3, nonsubjectibility to F exclusion and growth on Shigella sonneiD2371-48 (M. Pajunen, S. Kiljunen, and M. Skurnik, J. Bacteriol. 182:5114–5120, 2000). These findings indicate that φYeO3-12 is a T3-like phage that has adapted to Y. enterocolitica O:3 or vice versa. This is the first dsDNA yersiniophage genome sequence to be reported.

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7

Serwer, Philip, Elena T. Wright, Guimei Yu, and Wen Jiang. "30 Illuminating obscure states of the phage T3 DNA packaging motor." Journal of Biomolecular Structure and Dynamics 33, sup1 (May 18, 2015): 17–18. http://dx.doi.org/10.1080/07391102.2015.1032570.

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8

Serwer, Philip, Elena T. Wright, Borries Demeler, and Wen Jiang. "States of phage T3/T7 capsids: buoyant density centrifugation and cryo-EM." Biophysical Reviews 10, no. 2 (December 14, 2017): 583–96. http://dx.doi.org/10.1007/s12551-017-0372-5.

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9

Krüger, D. H., Sigrid Hansen, and Cornelia Schroeder. "Virus adaptation to host cells: The non-classical modification of phage T3." Zeitschrift für allgemeine Mikrobiologie 20, no. 8 (January 24, 2007): 495–502. http://dx.doi.org/10.1002/jobm.19800200803.

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10

Carrascosa, José L., José M. Valpuesta, and Hisao Fujisawa. "Three-Dimensional Structure of Cloned T3 Connector Protein at 1.6nm Resolution." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 1 (August 12, 1990): 282–83. http://dx.doi.org/10.1017/s0424820100180161.

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The head to tail connector of bacteriophages plays a fundamental role in the assembly of viral heads and DNA packaging. In spite of the absence of sequence homology, the structure of connectors from different viruses (T4, Ø29, T3, P22, etc) share common morphological features, that are most clearly revealed in their three-dimensional structure. We have studied the three-dimensional reconstruction of the connector protein from phage T3 (gp 8) from tilted view of two dimensional crystals obtained from this protein after cloning and purification.DNA sequences including gene 8 from phage T3 were cloned, into Bam Hl-Eco Rl sites down stream of lambda promotor PL, in the expression vector pNT45 under the control of cI857. E R204 (pNT89) cells were incubated at 42°C for 2h, harvested and resuspended in 20 mM Tris HC1 (pH 7.4), 7mM 2 mercaptoethanol, ImM EDTA. The cells were lysed by freezing and thawing in the presence of lysozyme (lmg/ml) and ligthly sonicated. The low speed supernatant was precipitated by ammonium sulfate (60% saturated) and dissolved in the original buffer to be subjected to gel nitration through Sepharose 6B, followed by phosphocellulose colum (Pll) and DEAE cellulose colum (DE52). Purified gp8 appeared at 0.3M NaCl and formed crystals when its concentration increased above 1.5 mg/ml.

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11

Serwer, Philip, and Elena T. Wright. "ATP-Driven Contraction of Phage T3 Capsids with DNA Incompletely Packaged In Vivo." Viruses 9, no. 5 (May 19, 2017): 119. http://dx.doi.org/10.3390/v9050119.

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12

Serwer, Philip, and Elena T. Wright. "Agarose gel electrophoresis reveals structural fluidity of a phage T3 DNA packaging intermediate." ELECTROPHORESIS 33, no. 2 (January 2012): 352–65. http://dx.doi.org/10.1002/elps.201100326.

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13

Garcia, Emilio, Jeffrey M. Elliott, Erlan Ramanculov, Patrick S. G. Chain, May C. Chu, and Ian J. Molineux. "The Genome Sequence of Yersinia pestis Bacteriophage φA1122 Reveals an Intimate History with the Coliphage T3 and T7 Genomes." Journal of Bacteriology 185, no. 17 (September 1, 2003): 5248–62. http://dx.doi.org/10.1128/jb.185.17.5248-5262.2003.

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ABSTRACT The genome sequence of bacteriophage φA1122 has been determined. φA1122 grows on almost all isolates of Yersinia pestis and is used by the Centers for Disease Control and Prevention as a diagnostic agent for the causative agent of plague. φA1122 is very closely related to coliphage T7; the two genomes are colinear, and the genome-wide level of nucleotide identity is about 89%. However, a quarter of the φA1122 genome, one that includes about half of the morphogenetic and maturation functions, is significantly more closely related to coliphage T3 than to T7. It is proposed that the yersiniophage φA1122 recombined with a close relative of the Y. enterocolitica phage φYeO3-12 to yield progeny phages, one of which became the classic T3 coliphage of Demerec and Fano (M. Demerec and U. Fano, Genetics 30:119-136, 1945).

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Serwer, Philip, Barbara Hunter, and Elena T. Wright. "Electron Microscopy of In-Plaque Phage T3 Assembly: Proposed Analogs of Neurodegenerative Disease Triggers." Pharmaceuticals 13, no. 1 (January 18, 2020): 18. http://dx.doi.org/10.3390/ph13010018.

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Increased knowledge of virus assembly-generated particles is needed for understanding both virus assembly and host responses to virus infection. Here, we use a phage T3 model and perform electron microscopy (EM) of thin sections (EM-TS) of gel-supported T3 plaques formed at 30 °C. After uranyl acetate/lead staining, we observe intracellular black particles, some with a difficult-to-see capsid. Some black particles (called LBPs) are larger than phage particles. The LBP frequency is increased by including proflavine, a DNA packaging inhibitor, in the growth medium and increasing plaque-forming temperature to 37 °C. Acidic phosphotungstate-precipitate (A-PTA) staining causes LBP substitution by black rings (BRs) that have the size and shape expected of hyper-expanded capsid containers for LBP DNA. BRs are less frequent in liquid cultures, suggesting that hyper-expanded capsids evolved primarily for in-gel (e.g., in-biofilm) propagation. BR-specific A-PTA staining and other observations are explained by α-sheet intense structure of the major subunit of hyper-expanded capsids. We hypothesize that herpes virus triggering of neurodegenerative disease occurs via in-gel propagation-promoted (1) generation of α-sheet intense viral capsids and, in response, (2) host production of α-sheet intense, capsid-interactive, innate immunity amyloid protein that becomes toxic. We propose developing viruses that are therapeutic via detoxifying interaction with this innate immunity protein.

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Lin, Tiao-Yin, Yi-Haw Lo, Pin-Wei Tseng, Shun-Fu Chang, Yann-Tsyr Lin, and Ton-Seng Chen. "A T3 and T7 Recombinant Phage Acquires Efficient Adsorption and a Broader Host Range." PLoS ONE 7, no. 2 (February 9, 2012): e30954. http://dx.doi.org/10.1371/journal.pone.0030954.

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Mancuso, Francesco, Jiahui Shi, and Danish Malik. "High Throughput Manufacturing of Bacteriophages Using Continuous Stirred Tank Bioreactors Connected in Series to Ensure Optimum Host Bacteria Physiology for Phage Production." Viruses 10, no. 10 (October 1, 2018): 537. http://dx.doi.org/10.3390/v10100537.

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Future industrial demand for large quantities of bacteriophages e.g., for phage therapy, necessitates the development of scalable Good Manufacturing Practice compliant (cGMP) production platforms. The continuous production of high titres of E coli T3 phages (1011 PFU mL−1) was achieved using two continuous stirred tank bioreactors connected in series, and a third bioreactor was used as a final holding tank operated in semi-batch mode to finish the infection process. The first bioreactor allowed the steady-state propagation of host bacteria using a fully synthetic medium with glucose as the limiting substrate. Host bacterial growth was decoupled from the phage production reactor downstream of it to suppress the production of phage-resistant mutants, thereby allowing stable operation over a period of several days. The novelty of this process is that the manipulation of the host reactor dilution rates (range 0.1–0.6 hr−1) allows control over the physiological state of the bacterial population. This results in bacteria with considerably higher intracellular phage production capability whilst operating at high dilution rates yielding significantly higher overall phage process productivity. Using a pilot-scale chemostat system allowed optimisation of the upstream phage amplification conditions conducive for high intracellular phage production in the host bacteria. The effect of the host reactor dilution rates on the phage burst size, lag time, and adsorption rate were evaluated. The host bacterium physiology was found to influence phage burst size, thereby affecting the productivity of the overall process. Mathematical modelling of the dynamics of the process allowed parameter sensitivity evaluation and provided valuable insights into the factors affecting the phage production process. The approach presented here may be used at an industrial scale to significantly improve process control, increase productivity via process intensification, and reduce process manufacturing costs through process footprint reduction.

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Zhou, Y., T. J. Giordano, R. K. Durbin, and W. T. McAllister. "Synthesis of functional mRNA in mammalian cells by bacteriophage T3 RNA polymerase." Molecular and Cellular Biology 10, no. 9 (September 1990): 4529–37. http://dx.doi.org/10.1128/mcb.10.9.4529-4537.1990.

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We found that the 5' nontranslated leader sequence from encephalomyocarditis virus (EMCV) allowed transcripts that were synthesized by the T3 RNA polymerase in mammalian cells to be translated in a cap-independent fashion. Stable mouse cell lines that carry the T3 RNA polymerase gene expressed the chloramphenicol acetyltransferase (CAT) gene under the control of a phage promoter when the CAT gene was fused to the EMCV leader and introduced into the cells by transient DNA uptake. The level of gene expression in such cells was similar to or greater than that observed with a conventional transient expression vector that is dependent on transcription by the host RNA polymerase II. Expression of the EMCV-CAT fusion gene was stimulated by cotransfection of the cells with a gene that encodes the poliovirus protease 2A protein (which inhibits cap-dependent translation), demonstrating that the EMCV-CAT fusion gene was expressed in a cap-independent fashion. Introduction of both the T3 RNA polymerase gene and the EMCV-CAT fusion gene into a variety of cultured mammalian cell lines (HeLa, BSC40, Ltk-, NIH 3T3, and C127) demonstrated that the T3-EMCV expression system functions in a broad range of cell types.

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Zhou, Y., T. J. Giordano, R. K. Durbin, and W. T. McAllister. "Synthesis of functional mRNA in mammalian cells by bacteriophage T3 RNA polymerase." Molecular and Cellular Biology 10, no. 9 (September 1990): 4529–37. http://dx.doi.org/10.1128/mcb.10.9.4529.

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We found that the 5' nontranslated leader sequence from encephalomyocarditis virus (EMCV) allowed transcripts that were synthesized by the T3 RNA polymerase in mammalian cells to be translated in a cap-independent fashion. Stable mouse cell lines that carry the T3 RNA polymerase gene expressed the chloramphenicol acetyltransferase (CAT) gene under the control of a phage promoter when the CAT gene was fused to the EMCV leader and introduced into the cells by transient DNA uptake. The level of gene expression in such cells was similar to or greater than that observed with a conventional transient expression vector that is dependent on transcription by the host RNA polymerase II. Expression of the EMCV-CAT fusion gene was stimulated by cotransfection of the cells with a gene that encodes the poliovirus protease 2A protein (which inhibits cap-dependent translation), demonstrating that the EMCV-CAT fusion gene was expressed in a cap-independent fashion. Introduction of both the T3 RNA polymerase gene and the EMCV-CAT fusion gene into a variety of cultured mammalian cell lines (HeLa, BSC40, Ltk-, NIH 3T3, and C127) demonstrated that the T3-EMCV expression system functions in a broad range of cell types.

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TSUCHIDA, SHIN-ICHI, HIDETAKE KOKUBO, MASAO TASAKA, and HISAO FUJISAWA. "DNA Sequences Responsible for Specificity of DNA Packaging and Phage Growth Interference of Bacteriophages T3 and T7." Virology 217, no. 1 (March 1996): 332–37. http://dx.doi.org/10.1006/viro.1996.0120.

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Dietz, A., H. Kossel, and R. Hausmann. "On the Evolution of the Terminal Redundancies of Klebsiella Phage No. 11 and of Coliphages T3 and T7." Journal of General Virology 66, no. 1 (January 1, 1985): 181–86. http://dx.doi.org/10.1099/0022-1317-66-1-181.

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21

Kiljunen, Saija, Heikki Vilen, Maria Pajunen, Harri Savilahti, and Mikael Skurnik. "Nonessential Genes of Phage φYeO3-12 Include Genes Involved in Adaptation to Growth on Yersinia enterocolitica Serotype O:3." Journal of Bacteriology 187, no. 4 (February 15, 2005): 1405–14. http://dx.doi.org/10.1128/jb.187.4.1405-1414.2005.

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ABSTRACT Bacteriophage φYeO3-12 is a T7/T3-related lytic phage that naturally infects Yersinia enterocolitica serotype O:3 strains by using the lipopolysaccharide O polysaccharide (O antigen) as its receptor. The phage genome is a 39,600-bp-long linear, double-stranded DNA molecule that contains 58 genes. The roles of many of the genes are currently unknown. To identify nonessential genes, the isolated phage DNA was subjected to MuA transposase-catalyzed in vitro transposon insertion mutagenesis with a lacZ′ gene-containing reporter transposon. Following electroporation into Escherichia coli DH10B and subsequent infection of E. coli JM109/pAY100, a strain that expresses the Y. enterocolitica O:3 O antigen on its surface, mutant phage clones were identified by their β-galactosidase activity, manifested as a blue color on indicator plates. Transposon insertions were mapped in a total of 11 genes located in the early and middle regions of the phage genome. All of the mutants had efficiencies of plating (EOPs) and fitnesses identical to those of the wild-type phage when grown on E. coli JM109/pAY100. However, certain mutants exhibited altered phenotypes when grown on Y. enterocolitica O:3. Transposon insertions in genes 0.3 to 0.7 decreased the EOP on Y. enterocolitica O:3, while the corresponding deletions did not, suggesting that the low EOP was not caused by inactivation of the genes per se. Instead, it was shown that in these mutants the low EOP was due to the delayed expression of gene 1, coding for RNA polymerase. On the other hand, inactivation of gene 1.3 or 3.5 by either transposon insertion or deletion decreased phage fitness when grown on Y. enterocolitica. These results indicate that φYeO3-12 has adapted to utilize Y. enterocolitica as its host and that these adaptations include the products of genes 1.3 and 3.5, DNA ligase and lysozyme, respectively.

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Abdelkader, Karim, Diana Gutiérrez, Agnieszka Latka, Dimitri Boeckaerts, Zuzanna Drulis-Kawa, Bjorn Criel, Hans Gerstmans, et al. "The Specific Capsule Depolymerase of Phage PMK34 Sensitizes Acinetobacter baumannii to Serum Killing." Antibiotics 11, no. 5 (May 17, 2022): 677. http://dx.doi.org/10.3390/antibiotics11050677.

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The rising antimicrobial resistance is particularly alarming for Acinetobacter baumannii, calling for the discovery and evaluation of alternatives to treat A. baumannii infections. Some bacteriophages produce a structural protein that depolymerizes capsular exopolysaccharide. Such purified depolymerases are considered as novel antivirulence compounds. We identified and characterized a depolymerase (DpoMK34) from Acinetobacter phage vB_AbaP_PMK34 active against the clinical isolate A. baumannii MK34. In silico analysis reveals a modular protein displaying a conserved N-terminal domain for anchoring to the phage tail, and variable central and C-terminal domains for enzymatic activity and specificity. AlphaFold-Multimer predicts a trimeric protein adopting an elongated structure due to a long α-helix, an enzymatic β-helix domain and a hypervariable 4 amino acid hotspot in the most ultimate loop of the C-terminal domain. In contrast to the tail fiber of phage T3, this hypervariable hotspot appears unrelated with the primary receptor. The functional characterization of DpoMK34 revealed a mesophilic enzyme active up to 50 °C across a wide pH range (4 to 11) and specific for the capsule of A. baumannii MK34. Enzymatic degradation of the A. baumannii MK34 capsule causes a significant drop in phage adsorption from 95% to 9% after 5 min. Although lacking intrinsic antibacterial activity, DpoMK34 renders A. baumannii MK34 fully susceptible to serum killing in a serum concentration dependent manner. Unlike phage PMK34, DpoMK34 does not easily select for resistant mutants either against PMK34 or itself. In sum, DpoMK34 is a potential antivirulence compound that can be included in a depolymerase cocktail to control difficult to treat A. baumannii infections.

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Serwer, Philip, and Elena T. Wright. "A Protein Assembly Hypothesis for Population-Specific Decrease in Dementia with Time." Biophysica 1, no. 1 (February 7, 2021): 15–21. http://dx.doi.org/10.3390/biophysica1010002.

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A recent report in the journal, Neurology, documents age-normalized, nation-specific (e.g., United States and Western Europe), progressive decrease of dementia, beginning about 25 years ago. This observation has, thus far, not had explanation. We begin our proposed explanation with the following previous disease construct. (1) Some dementia is caused by innate immune over-response to infections. (2) The innate immune over-response occurs via excessive conversion of amyloid protein to α-sheet conformation. (3) This conversion evolved to inhibit invading microbes by binding microbe-associated α-sheet, e.g., in hyper-expanded capsid intermediates of some viruses. The rarity of human α-sheet makes this inhibition specific for microbial invaders. As foundation, here we observe directly, for the first time, extreme, sheet-like outer shell thinness in a hyper-expanded capsid of phage T3. Based on phage/herpesvirus homology, we propose the following. The above decrease in dementia is caused by varicella-zoster virus (VZV) vaccination, USFDA-approved about 25 years ago; VZV is a herpesvirus and causes chickenpox and shingles. In China and Japan, a cotemporaneous non-decrease is explained by lower anti-VZV vaccination. Co-assembly extension of α-sheet is relatively independent of amino acid sequence. Thus, we project that additional dementia is suppressible by vaccination against other viruses, including other herpesviruses.

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Plotka, Magdalena, Anna-Karina Kaczorowska, Aleksandra Stefanska, Agnieszka Morzywolek, Olafur H. Fridjonsson, Stanislaw Dunin-Horkawicz, Lukasz Kozlowski, et al. "Novel Highly Thermostable Endolysin from Thermus scotoductus MAT2119 Bacteriophage Ph2119 with Amino Acid Sequence Similarity to Eukaryotic Peptidoglycan Recognition Proteins." Applied and Environmental Microbiology 80, no. 3 (November 22, 2013): 886–95. http://dx.doi.org/10.1128/aem.03074-13.

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ABSTRACTIn this study, we present the discovery and characterization of a highly thermostable endolysin from bacteriophage Ph2119 infectingThermusstrain MAT2119 isolated from geothermal areas in Iceland. Nucleotide sequence analysis of the 16S rRNA gene affiliated the strain with the speciesThermus scotoductus. Bioinformatics analysis has allowed identification in the genome of phage 2119 of an open reading frame (468 bp in length) coding for a 155-amino-acid basic protein with anMrof 17,555. Ph2119 endolysin does not resemble any known thermophilic phage lytic enzymes. Instead, it has conserved amino acid residues (His30, Tyr58, His132, and Cys140) that form a Zn2+binding site characteristic of T3 and T7 lysozymes, as well as eukaryotic peptidoglycan recognition proteins, which directly bind to, but also may destroy, bacterial peptidoglycan. The purified enzyme shows high lytic activity toward thermophiles, i.e.,T. scotoductus(100%),Thermus thermophilus(100%), andThermus flavus(99%), and also, to a lesser extent, toward mesophilic Gram-negative bacteria, i.e.,Escherichia coli(34%),Serratia marcescens(28%),Pseudomonas fluorescens(13%), andSalmonella entericaserovar Panama (10%). The enzyme has shown no activity against a number of Gram-positive bacteria analyzed, with the exception ofDeinococcus radiodurans(25%) andBacillus cereus(15%). Ph2119 endolysin was found to be highly thermostable: it retains approximately 87% of its lytic activity after 6 h of incubation at 95°C. The optimum temperature range for the enzyme activity is 50°C to 78°C. The enzyme exhibits lytic activity in the pH range of 6 to 10 (maximum at pH 7.5 to 8.0) and is also active in the presence of up to 500 mM NaCl.

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Sitzmann, J. H., and P. K. LeMotte. "Rapid and efficient generation of PCR-derived riboprobe templates for in situ hybridization histochemistry." Journal of Histochemistry & Cytochemistry 41, no. 5 (May 1993): 773–76. http://dx.doi.org/10.1177/41.5.7682230.

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In situ hybridization histochemistry (ISH) using cRNA probes (riboprobes) has become a powerful technique for the examination of gene expression in tissue sections. The construction of plasmid templates for the synthesis of riboprobes with phage RNA polymerases is often a difficult and time-consuming step. We have therefore developed a rapid, efficient, and flexible method to generate totally artificial riboprobe templates by the polymerase chain reaction (PCR). We have made riboprobe templates using self-priming oligonucleotide primers spanning 146 BP of the 3' end of the human cytokeratin 1 (K1) gene coding region flanked by T7 and T3 promoters. These PCR-derived riboprobe templates were used to synthesize 35S-labeled anti-sense riboprobes as well as sense riboprobes as negative controls. The riboprobes were then applied in ISH to human skin sections made from routinely fixed and paraffin-embedded clinical biopsy material. Consistent with published results, we observed strong expression of K1 mRNA in the suprabasal cell layers of the epidermis but only weak to undetectable signals in the basal and cornified cell layers and in the dermis. With this experimental procedure we see no decrease in probe efficiency or quality compared to conventional methods. The use of PCR-derived riboprobe templates for ISH makes it possible to detect expression of any desired gene of known sequence rapidly and efficiently.

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Scholz, D., S. Hansen, and H. A. Rosenthal. "Untersuchungen an T3-Phagen. IV. Isolierung temperatursensitiver Mutanten des Phagen T3 und ihre partielle Charakterisierung." Zeitschrift für allgemeine Mikrobiologie 13, no. 5 (January 24, 2007): 425–37. http://dx.doi.org/10.1002/jobm.19730130507.

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Aidar, Luis Antonio de Arruda, Marcio Abrahao, Helio K. Yamashita, and Gladys Cristina Dominguez. "Morphological Changes of Condyles and Helkimo Clinical Dysfunction Index in Patients Treated with Herbst - Orthodontic Appliance." Brazilian Dental Journal 24, no. 4 (July 2013): 313–21. http://dx.doi.org/10.1590/0103-6440201302114.

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This study evaluated the morphological changes in the temporomandibular joint (TMJ) condyles and calculated the Helkimo clinical dysfunction index (CDI) in adolescents with Class II Division 1 malocclusion and mandibular retrognathism treated with the Herbst appliance (phase I) and fixed orthodontic appliances (phase II). Thirty-two consecutive adolescents underwent phase I, and 23 completed phase II. The TMJs were evaluated qualitatively using magnetic resonance imaging (MRI) at the beginning of treatment (T1), during phase I (T2), at the end of phase I (T3) and at the end of phase II (T4). The CDI was calculated at T1, T3 and T4. From T1 to T3 (p=0.326), there were no changes in condyle morphology in 86.0% of the TMJs. From T3 to T4 (p<0.05) and T1 to T4 (p<0.05), changes occurred in 39.1% and 43.4% of the condyles. No significant changes in CDI occurred from T1 to T3, T3 to T4 and T1 to T4 (p=1.000; 86.6%, 76.2% and 76.2% concordance). After phase I, there were practically no changes in condyle morphology. At the end of phase II, a mild flattening was observed in some condyles. It may be concluded that no significant changes occurred in CDI after both treatment phases.

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Brtko, J., P. Filipčík, J. Knopp, and V. Sedláková. "Thyroid hormone responsiveness of the L1210 murine leukemia cell line." Acta Endocrinologica 126, no. 4 (April 1992): 374–77. http://dx.doi.org/10.1530/acta.0.1260374.

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The presence of saturable and high affinity 3,5,3′-triiodothyronine (T3) binding sites was demonstrated in LI 210 murine leukemia cell nuclei. Scatchard analysis revealed one class of receptors for T3 with Ka = 2.187 × 109l/mol and a maximum binding capacity (Bmax) of 3.96 fmol/106 cells. The effects of T3 on protein phosphorylation and growth rate of L1210 cells were investigated in a medium containing T3-depleted fetal calf serum. T3 was observed to be effective in enhancing protein phosphorylation (153.06%±5.99 sd) compared to cells grown in the absence of T3 (81.49%±13.50 sd). Moreover, in the presence of high T3 concentration (11.15 nmol/l) T3 was found to significantly increase the cell growth rate. In addition, the T3 receptor-associated alterations during the cell cycle, as measured by flow cytometry, suggest that the presence of T3 receptors becomes evident during the late G3 phase of the cell cycle, and T3 receptor numbers increase during the S phase. These results suggest that in in vitro conditions representing high T3 concentration, the number of L1210 leukemia cells may be increased by T3 via nuclear receptors. The L1210 leukemia cell line may serve as a convenient tool for in vitro studies of nuclear receptors and/or mechanism of action of T3. The binding affinity of T3 receptors is similar to that found in rat hepatocytes or human lymphocytes.

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29

Vigorito, Fabio de Abreu, Gladys Cristina Dominguez, and Luís Antônio de Arruda Aidar. "Dental and skeletal changes in patients with mandibular retrognathism following treatment with Herbst and pre-adjusted fixed appliance." Dental Press Journal of Orthodontics 19, no. 1 (January 2014): 46–54. http://dx.doi.org/10.1590/2176-9451.19.1.046-054.oar.

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OBJECTIVE: To assess the dentoskeletal changes observed in treatment of Class II, division 1 malocclusion patients with mandibular retrognathism. Treatment was performed with the Herbst orthopedic appliance during 13 months (phase I) and pre-adjusted orthodontic fixed appliance (phase II). METHODS: Lateral cephalograms of 17 adolescents were taken in phase I onset (T1) and completion (T2); in the first thirteen months of phase II (T3) and in phase II completion (T4). Differences among the cephalometric variables were statistically analyzed (Bonferroni variance and multiple comparisons). RESULTS: From T1 to T4, 42% of overall maxillary growth was observed between T1 and T2 (P < 0.01), 40.3% between T2 and T3 (P < 0.05) and 17.7% between T3 and T4 (n.s.). As for overall mandibular movement, 48.2% was observed between T1 and T2 (P < 0.001) and 51.8% between T2 and T4 (P < 0.01) of which 15.1% was observed between T2 and T3 (n.s.) and 36.7% between T3 and T4 (P < 0.01). Class II molar relationship and overjet were properly corrected. The occlusal plane which rotated clockwise between T1 and T2, returned to its initial position between T2 and T3 remaining stable until T4. The mandibular plane inclination did not change at any time during treatment. CONCLUSION: Mandibular growth was significantly greater in comparison to maxillary, allowing sagittal maxillomandibular adjustment. The dentoalveolar changes (upper molar) that overcorrected the malocclusion in phase I, partially recurred in phase II, but did not hinder correction of the malocclusion. Facial type was preserved.

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Nagasawa, T., K. Ichikawa, K. Minemura, M. Hara, H. Yajima, A. Sakurai, H. Kobayashi, K. Hiramatsu, S. Shigematsu, and K. Hashizume. "Differences in cellular transport of tri-iodothyronine and thyroxine: cell cycle-dependent alteration of tri-iodothyronine uptake." Journal of Endocrinology 147, no. 3 (December 1995): 479–85. http://dx.doi.org/10.1677/joe.0.1470479.

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Abstract Cellular and nuclear uptake of tri-iodothyronine (T3) and thyroxine (T4) was examined using the cultured cell line derived from rat liver, clone 9, and rat hepatoma, dRLH-84. The saturable cellular uptake of T3 and T4 was demonstrated in these cells. First we examined the cell cycle-dependent alteration of thyroid hormone uptake. Cellular T3 uptake was minimal in the early G1 phase and increased in the late G1 phase, reaching a maximal level in the S phase. Alterations in nuclear T3 uptake were in accordance with the changes in cellular T3 uptake. On the other hand, cellular and nuclear T4 uptake was unchanged throughout the cell cycle, suggesting the T3 specificity of the cell cycle-dependent alteration of cellular hormone transport. Next we examined the effect of sodium butyrate on the cellular transport of thyroid hormones. After treatment with 5 mm sodium butyrate, cellular and nuclear uptake of T3 was increased, reaching a maximal level (four- to sevenfold increase) after 48 h. When cells were incubated for 48 h with various concentrations of sodium butyrate, T3 uptake was enhanced by 1 mm sodium butyrate, reaching a maximal level with 5 mm. Although cellular T4 uptake was also increased after treatment with sodium butyrate, the degree and time-course of the increase were different from those of T3. The maximal increase in cellular T4 uptake (two- to threefold increase) was attained 20 h after treatment. Despite the increase in cellular T4 uptake, nuclear T4 uptake was decreased after treatment with sodium butyrate. For both T3 and T4, the enhanced cellular uptake was due to the increased Vmax without changes in the Michaelis–Menten constant. These data indicate that cellular transport of T4 is different from that of T3 in rat hepatic cells. Journal of Endocrinology (1995) 147, 479–485

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31

Kakabakos, S. E., G. P. Evangelatos, and D. S. Ithakissios. "Immunoadsorption of IgG onto second antibody covalently attached to Amino-Dylark beads for radioimmunoassays." Clinical Chemistry 36, no. 3 (March 1, 1990): 497–500. http://dx.doi.org/10.1093/clinchem/36.3.497.

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Abstract We present a solid-phase immobilization method for radioligand assays, using an immunoadsorption coating procedure of anti-triiodothyronine rabbit IgG (anti-T3 IgG) onto second antibody (sheep anti-rabbit IgG) covalently bound to Amino-Dylark beads. The second antibody was in excess, compared with the first antibody, thus eliminating reproducibility problems between immunoadsorptions. Beads coated with second antibody can be used to immobilize a variety of antigen-specific first antibodies. The amount of anti-T3 antibody required for solid-phase T3 radioimmunoassay (RIA) was only 10% more, per assay tube, than that utilized in liquid-phase T3 RIA, in which polyethylene glycol solution was the separation reagent; characteristics of assay performance were comparable. The immobilization procedure requires high-titer antisera or antigen-specific IgG and seems advantageous because of the decrease in antibody requirements without significant modification of antibody functionality.

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32

Lariviere, F., R. Moussalli, and D. R. Garrel. "Increased leucine flux and leucine oxidation during the luteal phase of the menstrual cycle in women." American Journal of Physiology-Endocrinology and Metabolism 267, no. 3 (September 1, 1994): E422—E428. http://dx.doi.org/10.1152/ajpendo.1994.267.3.e422.

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Possible changes in protein metabolism during the menstrual cycle were examined in eight healthy women who received an intravenous infusion of L-[1-13C]leucine on time during the follicular phase of the menstrual cycle and one time during the luteal phase. Enrichment of plasma [13C]ketoisocaproate and expired 13CO2 were measured to determine leucine flux and oxidation. Continuous respiratory gas exchange measurements were made for the determination of CO2 production, O2 uptake, and energy expenditure. The day of the tests, plasma thyroid hormone concentrations were measured as well as plasma and urinary cortisol. Leucine flux was higher during the luteal than during the follicular phase (2.25 +/- 0.39 vs 2.01 +/- 0.42 mumol.kg-1.min-1; P < 0.01), and leucine oxidation was also increased during the luteal phase [0.52 +/- 0.14 vs. 0.44 +/- 0.05 mumol.kg-1.min-1 (P < 0.05) for luteal and follicular phases, respectively]. Resting energy expenditure was increased during the luteal phase compared with the follicular phase (218 +/- 22 and 199 +/- 12 kJ/h, respectively). Plasma free triiodothyronine (T3) and the ratio triiodothyronine/reverse triiodothyronine (T3/rT3) were both significantly higher during the luteal phase [7.7 +/- 0.6 vs. 7.1 +/- 0.8 and 4.65 +/- 0.80 vs. 3.93 +/- 0.70 for T3 and T3/rT3, respectively (P < 0.05 for both comparisons)]. This study shows small changes in protein metabolism during the menstrual cycle in women, with an increase in oxidative leucine metabolism during the luteal phase. The concomitant increase observed in circulating free T3 raises the possibility that fluctuations in protein metabolism and thyroid hormones throughout the menstrual cycle are causally related.

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33

Ichikawa, K., K. Hashizume, T. Miyamoto, Y. Nishii, K. Yamauchi, H. Ohtsuka, and T. Yamada. "Conformational transition of thyroid hormone receptor upon hormone binding: demonstration by aqueous two-phase partitioning." Journal of Endocrinology 119, no. 3 (December 1988): 431–37. http://dx.doi.org/10.1677/joe.0.1190431.

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ABSTRACT An aqueous two-phase partitioning study of partially purified nuclear thyroid hormone receptor from rat liver was performed. Stability of 3,5,3′-tri-iodo-l-thyronine (T3)–receptor complex and T3-binding activity in the presence of dextran or polyethylene glycol were assessed in order to determine the amount of occupied or unoccupied receptors in each phase. Partition coefficients were calculated as the ratio of receptor concentration in the upper polyethylene glycol-rich phase H2O and that in the lower dextranrich phase H2O. The partition coefficient was a sensitive function of the salt at pH above 6·1 and below 5·1. The salt had no effect on the partition coefficient at pH around 5·6. These results suggest that the isoelectric point of the thyroid hormone receptor is about 5·6, confirming previous determinations using isoelectric focusing. The partition coefficient of the receptor decreased upon T3 binding, regardless of the salt composition. In contrast, the partition coefficient of thyroxine-binding globulin increased upon T3 binding. Free T3 preferentially partitioned into the upper polyethylene glycol-rich phase and gave a partition coefficient higher than 1·0. These results strongly suggest that the decrease in the partition coefficient of the receptor upon hormone binding reflects conformational changes or changes in electrostatic properties of the receptor upon hormone binding. Such an alteration may be involved in biological activation of the receptor upon hormone binding. J. Endocr. (1988) 119, 431–437

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34

Pillai, M. R. A., Jyotsna Narayanan, J. H. Gupte, and R. S. Mani. "Solid phase radioimmunoassay of triiodothyronine (T3) using antibody coupled carboxymethylcellulose powder." Journal of Radioanalytical and Nuclear Chemistry Articles 116, no. 2 (December 1987): 317–23. http://dx.doi.org/10.1007/bf02035775.

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35

Piran, U., W. J. Riordan, and L. A. Livshin. "New noncompetitive immunoassays of small analytes." Clinical Chemistry 41, no. 7 (July 1, 1995): 986–90. http://dx.doi.org/10.1093/clinchem/41.7.986.

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Abstract We developed a novel noncompetitive immunoassay format for monoepitopic analytes and describe here a model assay for triiodothyronine (T3), performed on Ciba Corning's ACS:180 analyzer. Acridinium ester (AE)-labeled bivalent anti-T3 was incubated with the sample, producing AE-anti-T3/T3 complexes and unreacted AE-anti-T3. Controlled-pore glass particles (CPG) with immobilized diiodothyronine (T2) were then added in excess, to bind AE-anti-T3 possessing two unoccupied binding sites but not AE-anti-T3 bound to one or two T3 molecules. Paramagnetic particles (PMP) with immobilized anti-AE were then added to the same cuvette to capture AE-anti-T3/T3 complexes; AE-anti-T3 bound to the surface of CPG, however, was not captured, because of steric hindrance. After the incubation, the PMP was magnetically separated to remove the liquid phase and the suspended CPG from the cuvette. The chemiluminescence associate with the PMP remaining in the cuvette was then measured. This noncompetitive T3 assay exhibited a 10-fold lower detection limit than the equivalent competitive T3 assay, i.e., 0.3 vs pg/test. Imprecision (CV) in the clinically significant range was 6% or less. The assay also displayed two- to sevenfold lower cross-reactivities and a wider dynamic range.

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36

Lidón-Soto, Abel, Eva Núñez-Delegido, Iván Pastor-Martínez, Pedro Robles, and Víctor Quesada. "Arabidopsis Plastid-RNA Polymerase RPOTp Is Involved in Abiotic Stress Tolerance." Plants 9, no. 7 (July 2, 2020): 834. http://dx.doi.org/10.3390/plants9070834.

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Plastid gene expression (PGE) must adequately respond to changes in both development and environmental cues. The transcriptional machinery of plastids in land plants is far more complex than that of prokaryotes. Two types of DNA-dependent RNA polymerases transcribe the plastid genome: a multimeric plastid-encoded polymerase (PEP), and a monomeric nuclear-encoded polymerase (NEP). A single NEP in monocots (RPOTp, RNA polymerase of the T3/T7 phage-type) and two NEPs in dicots (plastid-targeted RPOTp, and plastid- and mitochondrial-targeted RPOTmp) have been hitherto identified. To unravel the role of PGE in plant responses to abiotic stress, we investigated if Arabidopsis RPOTp could function in plant salt tolerance. To this end, we studied the sensitivity of T-DNA mutants scabra3-2 (sca3-2) and sca3-3, defective in the RPOTp gene, to salinity, osmotic stress and the phytohormone abscisic acid (ABA) required for plants to adapt to abiotic stress. sca3 mutants were hypersensitive to NaCl, mannitol and ABA during germination and seedling establishment. Later in development, sca3 plants displayed reduced sensitivity to salt stress. A gene ontology (GO) analysis of the nuclear genes differentially expressed in the sca3-2 mutant (301) revealed that many significantly enriched GO terms were related to chloroplast function, and also to the response to several abiotic stresses. By quantitative RT-PCR (qRT-PCR), we found that genes LHCB1 (LIGHT-HARVESTING CHLOROPHYLL a/b-BINDING1) and AOX1A (ALTERNATIVE OXIDASE 1A) were respectively down- and up-regulated in the Columbia-0 (Col-0) salt-stressed plants, which suggests the activation of plastid and mitochondria-to-nucleus retrograde signaling. The transcript levels of genes RPOTp, RPOTmp and RPOTm significantly increased in these salt-stressed seedlings, but this enhanced expression did not lead to the up-regulation of the plastid genes solely transcribed by NEP. Similar to salinity, carotenoid inhibitor norflurazon (NF) also enhanced the RPOTp transcript levels in Col-0 seedlings. This shows that besides salinity, inhibition of chloroplast biogenesis also induces RPOTp expression. Unlike salt and NF, the NEP genes were significantly down-regulated in the Col-0 seedlings grown in ABA-supplemented media. Together, our findings demonstrate that RPOTp functions in abiotic stress tolerance, and RPOTp is likely regulated positively by plastid-to-nucleus retrograde signaling, which is triggered when chloroplast functionality is perturbed by environmental stresses, e.g., salinity or NF. This suggests the existence of a compensatory mechanism, elicited by impaired chloroplast function. To our knowledge, this is the first study to suggest the role of a nuclear-encoded plastid-RNA polymerase in salt stress tolerance in plants.

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37

Liu, Chi, Liyong Ma, Ziyong Zhang, Zhuo Fu, and Lijuan Liu. "Research on the Corrosion Fatigue Property of 2524-T3 Aluminum Alloy." Metals 11, no. 11 (November 1, 2021): 1754. http://dx.doi.org/10.3390/met11111754.

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The 2524-T3 aluminum alloy was subjected to fatigue tests under the conditions of R = 0, 3.5% NaCl corrosion solution, and the loading cycles of 106, and the S-N curve was obtained. The horizontal fatigue limit was 169 MPa, which is slightly higher than the longitudinal fatigue limit of 163 MPa. In addition, detailed microstructural analysis of the micro-morphological fatigue failure features was carried out. The influence mechanism of corrosion on the fatigue crack propagation of 2524-T3 aluminum alloy was discussed. The fatigue source characterized by cleavage and fracture mainly comes from corrosion pits, whose expansion direction is perpendicular to the principal stress direction. The stable propagation zone is characterized by strip fractures. The main feature of the fracture in the fracture zone is equiaxed dimples. The larger dimples are mixed with second-phase particles ranging in size from 1 to 5 μm. There is almost a one-to-one correspondence between the dimples and the second-phase particles. The fracture mechanism of 2524 alloy at this stage is transformed into a micro-holes connection mechanism, and the nucleation of micropores is mainly derived from the second-phase particles.

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38

DING, HANQIN, and JUN ZHANG. "EFFECT OF CORRELATED-HOPPING INTERACTION ON A ONE-DIMENSIONAL EXTENDED HUBBARD MODEL WITH SPIN-EXCHANGE INTERACTION." Modern Physics Letters B 26, no. 07 (March 20, 2012): 1150044. http://dx.doi.org/10.1142/s0217984911500448.

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By using the field-theoretical techniques combining bosonization with renormalization group, we study a one-dimensional (1D) model of interacting electrons with on-site repulsion (U > 0), nearest-neighbor (nn) exchange (J) and correlated-hopping (t2, t3) interactions at weak coupling. In the case of a half-filled band, the two-body interaction t2 does not influence phase diagram of the model, while the presence of three-body interaction t3 makes the physics of the system highly non-trivial. By a Hartree–Fock decoupling, the effects of t3 bring about hopping of pairs, V-like (nn Coulomb interaction) and isotropic exchange terms in the reduced model Hamiltonian. Interestingly, a negative t3 provides a possibility for the occurrence of the triplet superconductivity in 1D system with purely repulsive interactions (U, J > 0). The ground state phase diagram including the insulating and superconducting phases is discussed analytically.

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Kong, Wing May, Niamh M. Martin, Kirsty L. Smith, James V. Gardiner, Ian P. Connoley, David A. Stephens, Waljit S. Dhillo, Mohammad A. Ghatei, Caroline J. Small, and Stephen R. Bloom. "Triiodothyronine Stimulates Food Intake via the Hypothalamic Ventromedial Nucleus Independent of Changes in Energy Expenditure." Endocrinology 145, no. 11 (November 1, 2004): 5252–58. http://dx.doi.org/10.1210/en.2004-0545.

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Abstract Increased food intake is characteristic of hyperthyroidism, although this is presumed to compensate for a state of negative energy balance. However, here we show that the thyroid hormone T3 directly stimulates feeding at the level of the hypothalamus. Peripheral administration of T3 doubled food intake in ad libitum-fed rats over 2 h and induced expression of the immediate early gene, early growth response-1, in the hypothalamic ventromedial nucleus (VMN), whereas maintaining plasma-free T3 levels within the normal range. T3-induced feeding occurred without altering energy expenditure or locomotion. Injection of T3 directly into the VMN produced a 4-fold increase in food intake in the first hour. The majority of T3 in the brain is reported to be produced by tissue-specific conversion of T4 to T3 by the enzyme type 2 iodothyronine deiodinase (D2). Hypothalamic D2 mRNA expression showed a diurnal variation, with a peak in the nocturnal feeding phase. Hypothalamic D2 mRNA levels also increased after a 12- and 24-h fast, suggesting that local production of T3 may play a role in this T3 feeding circuit. Thus, we propose a novel hypothalamic feeding circuit in which T3, from the peripheral circulation or produced by local conversion, stimulates food intake via the VMN.

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40

Kakabakos, S. E., E. Livanlou, G. P. Evangelatos, and D. S. Ithakissios. "Immobilization of immunoglobulins onto surface-treated and untreated polystyrene beads for radioimmunoassays." Clinical Chemistry 36, no. 3 (March 1, 1990): 492–96. http://dx.doi.org/10.1093/clinchem/36.3.492.

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Abstract The immunoreactivity of anti-triiodothyronine (anti-T3) IgG, pretreated at acidic pH and adsorbed onto polystyrene beads, was significantly greater than that determined for native anti-T3 IgG immobilized at optimum pH 3.5. Acidic-pH-pretreated IgG, adsorbed at pH 7.0 onto ethanol-treated beads, had less immunoreactivity than that on untreated beads and gave values similar to those of native IgG adsorbed onto activated beads at pH 9.6. The rate of immobilization onto treated beads was significantly greater than onto untreated ones, and the binding was reproducible (intra- and inter-batch coating CV, 3.7-4.6% and 7.2%, respectively) and very resistant to successive washings. A post-washing incubation in 10 mg/L bovine serum albumin solution was required to eliminate the decreased immobilized immunoreactivity caused by some washing reagents. For solid-phase radioimmunoassays of T3, 40% less antibody was needed when acidic-pH-pretreated IgG was adsorbed onto untreated beads or when native IgG was adsorbed onto ethanol-treated beads, in comparison with native IgG adsorbed onto untreated beads. Results and assay characteristics with such beads were comparable with results for solid-phase and liquid-phase polyethylene glycol assay of T3.

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41

Piran, U., D. Silbert-Shostek, and E. H. Barlow. "Role of antibody valency in hapten-heterologous immunoassays." Clinical Chemistry 39, no. 5 (May 1, 1993): 879–83. http://dx.doi.org/10.1093/clinchem/39.5.879.

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Abstract We studied the effects of hapten heterology on immunoassays of triiodothyronine (T3), digoxin, and cortisol, in a format involving labeled monoclonal antibodies and immobilized, protein-conjugated ligands. Replacing the homologous conjugated ligands T3, digoxin, and cortisol with their respective analogs diiodothyronine, digitoxin, and corticosterone led in each case to a decrease in the midpoint of displacement (ED50) for the same zero-dose signal. The mechanism of this phenomenon was studied by converting the bivalent anti-T3 to a monovalent whole antibody (bispecific monoclonal anti-T3 x anti-glucose-6-phosphate dehydrogenase) by cell fusion. The monovalent antibody was effective as a tracer in the homologous T3 assay, but generated a very low zero-dose signal with the heterologous solid phase, thus precluding sensitivity enhancement. On the basis of these results and additional kinetic and double-labeling experiments, we propose that the use of hapten heterology relies on bivalent binding of the antibody to the solid phase to compensate for a lower intrinsic affinity. This binding mechanism leads to lower assay concentrations of the ternary complex analyte-labeled antibody-immobilized hapten, thereby providing enhanced sensitivity.

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Chapital, Alyssa D., Steven R. Hendrick, Larry Lloyd, and David Pieper. "The Effects of Triiodothyronine Augmentation on Antithrombin III Levels in Sepsis." American Surgeon 67, no. 3 (March 2001): 253–56. http://dx.doi.org/10.1177/000313480106700310.

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Sepsis and multisystem organ failure are often associated with disseminated intravascular coagulation and consumption of coagulation inhibitors such as antithrombin III (ATIII). The “sick euthyroid syndrome” is also seen in association with significant illnesses and consists of decreased levels of circulating triiodothyronine (T3). We evaluated whether T3 supplementation would affect ATIII levels in septic rats. Thirty Sprague-Dawley rats were divided into three groups: sham laparotomy (S) plus saline, cecal ligation and puncture (CLP) plus saline, and CLP plus T3 (3 ng/hour) via an osmotic minipump. Twenty-four hours after laparotomy blood was drawn, and T3 and ATIII levels were then compared with baseline values. T3 supplementation partially negated the sepsis-induced decrease in circulating T3 levels. The levels are expressed as percentage change from the levels before surgery (S, -12.9 ± 3.1; CLP, -60.0 ± 5.3; CLP + T3, -34.9 ± 4.3; mean ± standard error; P < 0.05). T3 supplementation also statistically changed the percentage difference in ATIII levels toward the control (S, 9.6 ± 2.8; CLP, - 37.9 ± 5.4; CLP + T3, -16.0 ± 4.5; mean ± standard error; P < 0.01). T3 supplementation reduced the sepsis-induced decrease in ATIII levels. Whether this was accomplished by decreased consumption or increased production of ATIII via the direct anabolic effect of T3 on acute-phase protein synthesis in the liver is unknown and warrants further investigation.

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43

Swamy, M. S., S. Abraham, and A. V. Ramachandran. "Serum T3 and T4 levels during tail regeneration in the gekkonid lizard Hemidactylus flaviviridis." Amphibia-Reptilia 14, no. 2 (1993): 149–53. http://dx.doi.org/10.1163/156853893x00318.

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AbstractCirculating levels of serum T3 and T4 have been assayed by radioimmunoassay during tail regeneration in the gekkonid lizard Hernidacylus flaviviridis. In general the level of serum T3 was lower than that of T4; both hormones showed phase-specific alterations. The immediate post-autotomy periods (first week) were marked by elevated T4 levels; the later phases of regeneration, corresponding to peak histodifferentiation (15-40 days), were marked by elevated T3 levels. These changes in serum T3 and T4 indicate the participation of the thyroid gland in lizard tail regeneration and are discussed in relation to changes in systemic, metabolic and haematologic variables characteristic of lizard tail regeneration.

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Cho, Heon Jae. "Long-Term Stability of Surgical Mandibular Setback." Angle Orthodontist 77, no. 5 (September 1, 2007): 851–56. http://dx.doi.org/10.2319/052306-209.1.

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Abstract Objective: To test the relationship between positional changes of the proximal segments during surgery and the positional rebound of the mandible during the postsurgical period of orthodontic treatment. Materials and Methods: The sample included records for 34 patients who had received sagittal split surgery for the correction of mandibular prognathism. Data were collected from standardized cephalometric radiographs taken immediately prior to surgery (T2), immediately following surgery (T3), and following the completion of orthodontic treatment (T4). Linear and angular changes in the orientation of the posterior border of the ascending ramus between time points T2, T3, and T4 were measured relative to superimposition on the anterior cranial base. In addition, linear changes in the position of pogonion between T3 and T4 were measured. Results: The magnitude of linear displacement of the posterior border of the proximal segment during surgery (T2 to T3) was statistically significantly correlated (r = .61) with the magnitude of linear displacement of pogonion during the postsurgical phase of orthodontic treatment (T3 to T4). There was a strong relationship between the magnitude of angular (r = .67) displacement of the posterior border of the proximal segments during surgery (T2 to T3) and the magnitude of angular rebound of the posterior border of the proximal segments that occurred during the postsurgical phase of orthodontic treatment (T3 to T4). Conclusions: When rigid fixation procedures alter the position of the proximal segments during sagittal split osteotomy of the mandible, the proximal segments tend to go back toward their presurgical positions following surgery.

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Brenta, Gabriela, Jorge Thierer, Marcela Sutton, Adriana Acosta, Nora Vainstein, Fernando Brites, Laura Boero, Leonardo Gómez Rosso, and Stefan Anker. "Low plasma triiodothyronine levels in heart failure are associated with a reduced anabolic state and membrane damage." European Journal of Endocrinology 164, no. 6 (June 2011): 937–42. http://dx.doi.org/10.1530/eje-11-0094.

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BackgroundLow plasma triiodothyronine (T3) levels are considered a prognostic predictor of death in heart failure (HF) patients.AimTo study an association between plasma T3 levels and several cardiac, neurohormonal, and metabolic markers of HF.MethodsA total of 133 ambulatory HF patients (114 males; mean age 63.2 years) with left ventricular ejection fraction <40% were enrolled. TSH, total tetraiodothyronine (T4) and T3, N-terminal pro-brain natriuretic peptide (NT-proBNP), and other cardiac and metabolic parameters were measured. The lowest tertile of T3 (group 1) was compared against the two upper ones (group 2).ResultsIn simple logistic regression, the lowest T3 tertile was associated with more advanced HF disease status: older (age: odds ratio (OR)=1.05; confidence interval (CI) 95% 1.01–1.09, P=0.004), lower functional capacity (walking test: OR=0.996; CI 95% 0.993–0.999, P=0.008), higher NT-proBNP (OR=1.64; CI 95% 1.19–2.27, P=0.003) and adiponectin levels (OR=1.07; CI 95% 1.02–1.11, P=0.004), lower DHEAS log-transformed (OR=0.50; CI 95% 0.31–0.80, P=0.004), and the presence of lower phase angle values as measured by body bioelectrical impedance analysis (OR=3.18; CI 95% 1.50–6.71, P=0.04) and worse renal function (OR=0.96; CI 95% 0.94–0.98, P=0.003). T3 levels in the lowest tertile were independently associated with low phase angle values (OR=2.95, CI 95% 1.16–7.50, P=0.02) and the log transformation of DHEAS (OR=0.56; CI 95% 0.32–0.97, P=0.04).ConclusionWe have demonstrated an association between plasma T3 levels in the lower range and other deranged hormonal and metabolic parameters in HF patients.

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Ślebodziński, A. B., and J. Twardon. "Thyroid hormones (th) and 5'-monodeiodinase (5'-md) activity in goat's milk from the early, mid- and late lactation period." Acta Veterinaria Hungarica 52, no. 3 (September 1, 2004): 349–59. http://dx.doi.org/10.1556/avet.52.2004.3.10.

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The physiological significance of thyroid hormones (TH) present in colostrum and milk is still under consideration. The present study was aimed at determining milk thyroxine (T4) and triiodothyronine (T3) levels in three lactation phases (early, mid- and late) of the goat, and to measure activity of the milk 5'-deiodinase (5'-MD) enzyme responsible for the intramammary conversion of pro-hormone T4 to its metabolically highly active form T3. Thirty-two milk goats (Polish White breed) fed a standard diet were used for milk sampling. The highest TH levels in mammary secretion were recorded during the first 2-3 days post partum. Then the hormone levels decreased, and by about Day 7 fluctuated around the overall mean for the early-lactation phase (Days 1 to 24 of lactation), recording 0.134 ± 0.059 µg T4 and 150.8 ± 2.80 ng T3 in 100 ml of the milk. Such T4 concentrations appeared to be comparable to those in the rabbit and human, whereas the concentration of T3 was higher than in the cow, pig and mare's milk. Milk 5'-MD activity was higher (P < 0.01) during early and late lactation, compared to the mid-lactation phase. It coincided with low T4 and high T3 milk levels during early lactation, and with high milk T4 and low T3 concentrations during late lactation. The quantity of T4 and T3 available to newborn kids in milk suggests that TH ingested with the colostrum may have a physiological role during the early postnatal life of suckling goats.

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Tannenbaum, Daniel, Kanwal Pratap Singh Raghav, Robert Asa Horn, Michael J. Overman, Cathy Eng, Scott Kopetz, Benny Johnson, et al. "Systematic review of three decades of clinical trials in metastatic colorectal cancer: Making lemonade out of lemons?" Journal of Clinical Oncology 37, no. 4_suppl (February 1, 2019): 656. http://dx.doi.org/10.1200/jco.2019.37.4_suppl.656.

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656 Background: Despite multiple trials of new agents in metastatic colorectal cancer (mCRC), long term outcomes remain poor. This study explores the changing trends in the design, interpretation and outcomes of phase III randomized controlled trials (RCT) in mCRC over time. Methods: Phase III RCTs of systemic therapy for mCRC with enrollment between 1986 and 2016 were identified through 4 electronic databases and grouped into 3 time periods (1986-1996 – T1; 1997-2006 – T2 & 2007-2016 – T3). Study selection, quality appraisal and data collection were performed by 2 independent investigators. Study characteristics, primary and secondary endpoints, and authors’ interpretation of results and conclusions were analyzed. Improvement in overall survival (OS) was the difference between experimental and control arms. A study was deemed positive if it met its end point, was recommended for further study or for adoption for clinical use (p ≤ 0.05 significant for all analyses). Results: One hundred fifty trials (T1=36, T2=62, T3=52) with 77494 patients (T1=12406, T2=39158, T3=25930) were included. Although 1st line therapy trials continued to be the most common across all T, the percentage (%) of trials evaluating 3rd line and beyond (T1=0, T2=3, T3=27) have increased significantly over time as have trials with targeted agents (T1=11, T2=34, T3=79). Although OS remains the most common primary end point, more trials in T2 & T3 have used progression-free survival instead (14 vs 47 & 44). The % of trials with negative results but interpreted as positive increased over time (T1=18; T2=42; T3=35). Across all T, the median improvement in OS (months, m) of these trials was significantly lower compared to the trials that met primary end point across all T (T1 = 0 vs 1.8 m, T2 = -0.1 vs 3.25, T3 = -0.25 vs 2.55). Conclusions: A significant shift has occurred over the past three decades in the design and interpretation of phase III trials in advanced CRC. Any interpretations of potential survival benefits from trials that have not met primary end point must be made with significant caution.

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Alqahtani, Abdullah Saad, Rajashekhara Bhari Sharanesha, Khalid Gufran, Nasser Raqe Alqhtani, Alwaleed Abushanan, Mohammed Alasqah, Abdulaziz Mohammad Alsakr, and Hassan Alkharaan. "Variation in Hemodynamic Characteristics during Periodontal Crown-Lengthening Surgical Procedure: An Uncontrolled Cohort Study." Healthcare 10, no. 5 (May 16, 2022): 919. http://dx.doi.org/10.3390/healthcare10050919.

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(1) Background: The purpose of this prospective study was to determine the changes in primary hemodynamic parameters and oxygen saturation in systemically healthy patients during the surgical procedure involving crown lengthening. (2) Methods: A total of 44 patients who required a crown-lengthening procedure in a single tooth in the maxillary arch were included in this study. Heart rate (HR), blood pressure (BP) and oxygen saturation (SpO2) were measured in all the subjects at three different intervals: before injecting the anesthetic (T1), after the anesthetic injection (T2) and after the procedure (T3). Descriptive statistics were computed, and observations were recorded as mean and standard deviation (SD). Analysis of variance (ANOVA) was used to compare the mean observation within parameters at different time intervals. (3) Results: All primary hemodynamic parameters were increased in the T2 phase over T1 and decreased in the T3 phase over T2. However, SpO2 decreased in both the T2 and T3 phases compared to the initial T1 phase. No significant differences were observed among the primary hemodynamic variables. However, SpO2 showed a significant difference (p = 0.013) among the T1, T2 and T3 phases. (4) Conclusions: Further study with larger sample size is required in order to analyze the accurate hemodynamic alterations.

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Wang, Chunming, Shuai Guo, Luming Zeng, Desen Zheng, Jianchao Xu, Munan Yang, and Tongxiang Liang. "Effects of Second Phases on Microstructure, Microhardness, and Corrosion Behavior of Mg-3Sn-(1Ca) Alloys." Materials 12, no. 16 (August 7, 2019): 2515. http://dx.doi.org/10.3390/ma12162515.

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The effects of second phases on microstructure, microhardness, and corrosion behavior of aged Mg-3Sn (T3) and Mg-3Sn-1Ca (TX31) alloys are investigated systematically. The thermal stability of the CaMgSn phase is higher than that of the Mg2Sn phase, and the microstructure remains essentially unchanged in the TX31 alloy after solution treatment for 28 h at 733 K. The T3 alloy exhibits double age-hardening peaks; one is 54.9 ± 2.1 HV for 7 h, and the other is 57.4 ± 2.8 HV for 15 h. However, the microhardness quickly reaches a stable value with increasing aging times in the TX31 alloy due to the no change in CaMgSn phases. It was also found by electrochemical impedance spectra that the corrosion resistance of aged T3 alloy is superior to that of aged TX31 alloy, especially T3 alloy aged for 7 h. The corrosion film of aged T3 alloy is denser, which attributes to most of dissolved Sn in the α-Mg matrix and the formation of a small quantity of tiny Mg2Sn particles, and effectively prevents the occurrence of further corrosion of the Mg matrix. However, galvanic cells formed between α-Mg and CaMgSn phases accelerate the corrosion of aged TX31 alloy.

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Ting, C. C., M. E. Hargrove, and Y. S. Yun. "Augmentation by anti-T3 antibody of the lymphokine-activated killer cell-mediated cytotoxicity." Journal of Immunology 141, no. 3 (August 1, 1988): 741–48. http://dx.doi.org/10.4049/jimmunol.141.3.741.

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Abstract This study showed that a mAb (145-2C11) against the T3 epsilon-chain of the TCR complex augmented the cytotoxic activity of the lymphokine-activated killer (LAK) effectors. The LAK cells were induced by culturing normal spleen cells with purified human rIL-2. Adding alpha T3 at the effector phase of the cytotoxic reactions augmented the LAK-mediated cytotoxicity. The alpha T3-augmented LAK killing was seen only with tumor targets, and there was no increase of killing against Con A-induced lymphoblasts. The augmentation effect was dose dependent on both the amounts of alpha T3 and the number of LAK cells added. A very low concentration of alpha T3 (1/10,000 dilution of culture supernatants) was sufficient to induce alpha T3-augmented LAK-mediated cytotoxicity. Human rIL-2 at 10 to 30 U/ml was sufficient to generate LAK cells for maximal alpha T3 augmentation, whereas 300 to 1000 U/ml of IL-2 were needed to generate maximal LAK activity when tested in the absence of alpha T3. LAK cells generated for longer periods of time showed a progressive increase of alpha T3-augmented cytotoxicity. For some targets, the alpha T3-augmented LAK killing was FcR dependent as evidenced by the ability of alpha FcR mAb 2.4G2 to inhibit, and for others it was not inhibited. The alpha T3-augmented killing did not correlate with the FcR expression on target cells as defined by 2.4G2. The LAK cells were both Lyt-2+ and Lyt-2-, but the LAK cells involved in alpha T3-augmented killing were exclusively Lyt-2+. Preincubation of LAK cells with alpha T3, but not preincubation of targets with alpha T3, resulted in augmented killing suggesting that the alpha T3 effect was unrelated to an antibody-dependent cell-mediated cytotoxicity. Our findings indicate that alpha T3 is a potent reagent to augment the cytotoxic reaction of LAK cells. These results suggested that a relationship might exist between the T3 complex and the cytotoxic activity of a subpopulation of Lyt-2+ LAK cells.

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Journal articles on the topic 'Phage T3'

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